For example, in Japanese Patent Application Publication (KOKAI) No. Hei 9-51309 there is proposed an inter-vehicle communication system, comprising: a forward light emitting/receiving unit for emitting or receiving a laser beam signal to and from a forward direction of a vehicle; a backward light emitting/receiving unit for emitting or receiving a laser beam signal to and from a backward direction of the vehicle; and signal relay means for relaying signals between the forward light emitting/receiving unit and the backward light emitting/receiving unit so that a laser beam signal including a signal received by the forward light emitting/receiving unit is transmitted from the backward light emitting/receiving unit, and that a laser beam signal including a signal received by the backward light emitting/receiving unit is transmitted from the forward light emitting/receiving unit, thereby enabling a progressive transmission of signals to be established between vehicles, and thereby even in such cases where, for example, a plurality of vehicles are lined up in queue in the forward direction due to a traffic congestion, where there is a too long inter-vehicle distance in a highway or the like, or where visibility between vehicles is deteriorated due to rains, fog or the like, it is ensured for specific information owned by a specific vehicle to be transferred to other vehicles.
Further, in Japanese Patent Application Publication (KOKAI) No. 2001-158390 there is disclosed inter-vehicle communication equipment having a transceiver capable of exchanging information between vehicles for use in a saddle-mount type vehicle, on which an operator ride on a saddle thereof. The inter-vehicle communication equipment is installed adjacent to lighting means in order easily to secure its installation space, in addition to facilitate adjustment of the position of the communication equipment, and thus to enable to improve reception performance thereof.
According to the inter vehicle communication system proposed by the Japanese Patent Application Publication (KOKAI) No. Hei 9-51309, because it transmits information between vehicles using a laser beam signal, it must have light emitting/receiving units for emitting a laser beam specific thereto provided at the front and the rear ends of the vehicle, thereby increasing the cost. Moreover, because this equipment carries out information transmission using the laser beam, if the laser beam emitted from the aforementioned light emitting/receiving unit impinges on a human body, this part of the body may possibly be damaged, thereby causing a safety problem.
Further, according to the inter-vehicle communication equipment disclosed in the Japanese Patent Application Publication (KOKAI) No. 2001-158390, because a separate transceiver must be installed adjacent to its lighting means, it requires a plurality of lighting means additionally, thereby complicating the equipment. And thus there is a disadvantage that the cost thereof increases.
The present invention is contemplated to solve the above-mentioned problems associated with the conventional art, and an object thereof is to provide a novel vehicle communication system, a vehicle, and vehicle communication equipment which enables vehicle communication using the light without requiring any new dedicated light emitting means.